CN103145406A - Method for preparing aluminum oxide ceramics with excellent wear-resisting property - Google Patents

Abstract

The invention discloses a method for preparing aluminum oxide ceramics with excellent wear-resisting property. The method comprises the steps of: (1) preparing for the following components of raw materials in percent by weight: 70-99 percent of Al2O3, 0.01-10 percent of rare earth yttrium compound and 0.19-20 percent of calcium compound or mineral, magnesium compound or mineral and silicon compound or mineral; (2) ball-milling the raw materials prepared in the step (1) for 4-96 h; (3) after drying the raw materials obtained in the step (2), preparing a blank body by adopting isostatic compaction, roller forming or axial extrusion forming; and (4) sintering the blank body at a temperature of 1150-1700 DEG C, preserving the temperature for 15-360 min and cooling to room temperature to prepare the finished product, wherein the sintering is pressureless sintering, and the sintering atmosphere is air atmosphere or reducing atmosphere. According to the method, through adding the rare earth yttrium compound and by adopting common industrial equipment, the process is simple; and compared with rare earth-free aluminum oxide ceramics, the aluminum oxide ceramics is low in sintering temperature and excellent in wear-resisting property.

Description

A kind of method for preparing the alumina-ceramic of wear resisting property excellence

Technical field

The present invention relates to a kind of aluminium oxide ceramic abrasive resistance that increases substantially, reduce simultaneously ceramic firing temperature, the method for the alumina-ceramic of preparation wear resisting property excellence.

Background technology

Use the earliest alumina-ceramic as tool material from Englishman in 1912, aluminum oxide sparking plug insulator is made by company of Siemens in 1931-Han Site, and since obtaining the alundum patent, the alumina-ceramic development obtains remarkable progress, becomes a kind of consumption maximum, the widest special ceramic material of use face.Only aspect the Wear-resistant engineering ceramic material, just relate to all multi-products such as cutting tool, various wear-resistant sandblast are chewed, wortle, wiredrawing step pulley, filar guide, bearing, axle sleeve, bearing ball, ball valve, grinding medium, be used in each fields such as metallurgy, light industry, chemical industry, electromechanics, boats and ships, aerospace.

For a long time, the various countries scientific research personnel has carried out large quantity research aspect the additive to affect Alumina Ceramics.Sintering aid, transition metal oxide and rare earth oxide are added in discovery in aluminum oxide, help to obtain desirable microstructure and improve ceramic performance.Fracture toughness property and the intensity in order to improve alumina ceramic material for example, people select to add a small amount of auxiliary agent, and these auxiliary agents grow into second-phase and reach toughness reinforcing purpose in sintering process.Mukhopadhyay etc. think Y ₂O ₃Solid solution can reduce the crystal boundary diffusivity, improve ceramic abrasive resistance.

At present, the developed country such as American-European and Japan is being in the first place in the world aspect the research of alumina-ceramic and production.China is alumina-ceramic big producing country, but quality product is still not high, and most products belongs to low-and-medium-grade products, and expensive goods mainly depends on import.The porcelain of for example weaving, homemade goods is in low grade, and every price several unit to ten are first not to be waited; The import porcelain piece of Japan, the product of 1 to 2 grammes per square metre, more than 200 yuan of price.Due to the attention degree of research not also or the backwardness of Technology makes China lag far behind developed country aspect the alumina-ceramic expensive goods, therefore, independently research and develop expensive goods very urgent.Studies show that in a large number, the wear resisting property of alumina-ceramic and the strength of materials, hardness, the microtexture of breaking property and material thereof have complicated relation.Improve the especially wear resisting property of alumina porcelain of alumina-ceramic, not yet can find satisfied solution at present.

Summary of the invention

The objective of the invention is for above-mentioned existing problems, a kind of aluminium oxide ceramic abrasive resistance that significantly improves is provided, reduce simultaneously the method for ceramic firing temperature, low cost is prepared the alumina-ceramic of excellent in abrasion resistance.

Concrete steps are:

(1) mass percentage content of each component of raw material is: Al ₂O ₃The compound of the compound 0.01-10% of 70-99.8%, rare-earth yttrium and the compound of calcium or mineral, magnesium or compound or the mineral 0.19-20% of mineral and silicon.

(2) the raw material ball milling that step (1) is prepared 4-96 hour.

(3) with after step (2) gained raw material drying, adopt isostatic pressing, roll forming or axial pressure moulding, make base substrate.

(4) base substrate at 1150-1700 ℃ of sintering, is sintered to pressureless sintering, and sintering atmosphere is air atmosphere or reducing atmosphere, is incubated 15-360 minute, is cooled to room temperature and makes finished product.

Described reducing atmosphere is a kind of in carbon dust, hydrogen, nitrogen and rare gas element.

The compound of described rare-earth yttrium is a kind of in yttrium oxide, six water Yttrium trinitrates, yttrium hydroxide, yttrium carbonate, Yttrium trichloride and yttrium oxalate.

The compound of described silicon is silicon-dioxide quality mark greater than 40% compound.

Described siliceous mineral are a kind of in natural quartz, talcum, diopside, the tremolite and kaolin.

The compound of described magnesium is magnesian massfraction greater than 40% compound.

The described mineral that contain magnesium are a kind of in rhombspar, magnesite and serpentine.

The compound of described calcium is that the massfraction of calcium oxide is greater than 50% compound.

The mineral of described calcic are a kind of in calcite, limestone and chalk rock.

(5) by standard: 1999 pairs of goods of JC/T848.1 – carry out the wear rate test.

Test result shows: the alumina ceramic material of developing reduces approximately 45% than the corresponding wear rate that does not contain the rare earth alumina stupalith is the highest, and firing temperature can reduce at most 30 ℃.

Main characteristics of the present invention is to adopt general industry equipment by adding the rare-earth yttrium compound, and technique is simple, and the alumina-ceramic of rare earth is not mixed in contrast, has prepared the product sintering temperature low, and the alumina-ceramic of wear resisting property excellence has application prospect.

Embodiment

Embodiment 1:

(1) mass percentage content of each component of raw material is: α-Al ₂O ₃Powder 93.5%, yttrium hydroxide 1.5%, kaolin 1.66%, calcium oxide 1.67% and magnesium oxide 1.67%.

(2) raw material that step (1) is prepared was put into the ball mill device ball milling 42 hours.

(3) with step (2) gained slurry through 110 ℃ of oven dry, 8 hours time.

(4) with step (3) gained powder through waiting static pressure (100MP) moulding, spherical base substrate is made in pressurize 10 minutes.

(5) with the spherical green compact of step (4) gained at 1450 ℃ of lower sintering of high temperature resistance furnace, sintering carries out in air atmosphere, is incubated 60 minutes, is down to room temperature and namely gets required wear-resisting alumina ceramic material, the specimen wear rate is 0.000552%h ^-1

Embodiment 2:

(1) mass percentage content of each component of raw material is: α-Al ₂O ₃Powder 96%, yttrium hydroxide 1.0%, kaolin 1.0%, calcium carbonate 1.0% and magnesium basic carbonate 1.0%.

(2) raw material that step (1) is prepared was put into the ball mill device ball milling 42 hours.

(3) with step (2) gained slurry through 110 ℃ of oven dry, 8 hours time.

(4) with step (3) gained powder through waiting static pressure (100MP) moulding, spherical base substrate is made in pressurize 10 minutes.

(5) with the spherical green compact of step (4) gained at 1480 ℃ of lower sintering of high temperature resistance furnace, sintering carries out in air atmosphere, is incubated 100 minutes, is down to room temperature and namely gets required wear-resisting alumina ceramic material, the specimen wear rate is 0.000447%h ^-1

Embodiment 3:

(1) mass percentage content of each component of raw material is: α-Al ₂O ₃Powder 95%, yttrium oxide 1.0%, kaolin 1.5%, calcium carbonate 1.5% and rhombspar 1.0%.

(2) raw material that step (1) is prepared was put into the ball mill device ball milling 42 hours.

(3) with step (2) gained slurry through 110 ℃ of oven dry, 8 hours time.

(4) with step (3) gained powder through waiting static pressure (100MP) moulding, spherical base substrate is made in pressurize 10 minutes.

(5) with the spherical green compact of step (4) gained at 1430 ℃ of lower sintering of high temperature resistance furnace, sintering carries out in air atmosphere, is incubated 120 minutes, is down to room temperature and namely gets required wear-resisting alumina ceramic material, the specimen wear rate is 0.000489%h ^-1

Comparative Examples:

(1) mass percentage content of each component of raw material is: α-Al ₂O ₃Powder 95%, kaolin 1.66%, calcium carbonate 1.67%, magnesium oxide 1.67%.

(2) raw material that step (1) is prepared was put into the ball mill device ball milling 42 hours.

(3) with step (2) gained slurry through 110 ℃ of oven dry, 8 hours time.

(4) with step (3) gained powder through waiting static pressure (100MP) moulding, spherical base substrate is made in pressurize 10 minutes.

At 1450 ℃ of lower sintering of high temperature resistance furnace, sintering carries out in air atmosphere with the spherical green compact of step (4) gained, is incubated 100 minutes, is down to room temperature and namely gets required wear-resisting alumina ceramic material, and the specimen wear rate is 0.000817%h ^-1

Claims (1)

1. method for preparing alumina-ceramic is characterized in that concrete steps are:

(1) mass percentage content of each component of raw material is: Al ₂O ₃The compound of the compound 0.01-10% of 70-99.8%, rare-earth yttrium and the compound of calcium or mineral, magnesium or compound or the mineral 0.19-20% of mineral and silicon;

(2) the raw material ball milling that step (1) is prepared 4-96 hour;

(3) with after step (2) gained raw material drying, adopt isostatic pressing, roll forming or axial pressure moulding, make base substrate;

(4) base substrate at 1150-1700 ℃ of sintering, is sintered to pressureless sintering, and sintering atmosphere is air atmosphere or reducing atmosphere, is incubated 15-360 minute, is cooled to room temperature and makes finished product;

Described reducing atmosphere is a kind of in carbon dust, hydrogen, nitrogen and rare gas element;

The compound of described rare-earth yttrium is a kind of in yttrium oxide, six water Yttrium trinitrates, yttrium hydroxide, yttrium carbonate, Yttrium trichloride and yttrium oxalate;

The compound of described silicon is silicon-dioxide quality mark greater than 40% compound;

Described siliceous mineral are a kind of in natural quartz, talcum, diopside, the tremolite and kaolin;

The compound of described magnesium is magnesian massfraction greater than 40% compound;

The described mineral that contain magnesium are a kind of in rhombspar, magnesite and serpentine;

The compound of described calcium is that the massfraction of calcium oxide is greater than 50% compound;

The mineral of described calcic are a kind of in calcite, limestone and chalk rock.